A groundbreaking approach to monoclonal protein identification

For patients at risk of plasma cell disorders, early identification is critical to ensure better outcomes. Coined as MASS-FIX, our innovative approach uses matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS), and marks the first major breakthrough in multiple myeloma screening since gel electrophoresis was developed in 1967. 



With MASS-FIX quantitation, the M-protein quantitation and isotyping will be performed at the same time; it is an improved methodology and provides a greater level of sensitivity to standard protein electrophoresis.

Key testing


  • Greater test sensitivity of monoclonal proteins. Mayo Clinic will be able to quantify to a lower threshold (LOQ of .0.01 g/dl) than traditional protein electrophoresis.
  • With greater sensitivity and specificity for quantification, clinicians can be even more confident when negative test results obtained.
  • The right test at the right time for your patients; ease of ordering and streamlined test menu for diagnosis and monitoring patients.
  • Testing approved and utilized by Mayo clinicians and myeloma experts; consistent with NCNN and IMWG guidelines.
  • Mayo Clinic has internally verified the equivalence of the M-protein measurements by this method to SPEP, involving over 6,300 comparisons of SPEP to new method. While the methods are equivalent, the analytical measuring range is significantly extended using QMPSS. Thus, providing better patient care.


Screening and diagnosis

We have developed an innovative method to accurately screen for monoclonal proteins and determine risk of progression that features a simplified approach to risk stratification and diagnosis using the Mayo Stratification for Myeloma and Risk-Adapted Therapy (mSMART).

Key testing

risk stratification

Our updated approach to fluorescence in-situ hybridization (FISH) testing takes into account the fact that multiple myeloma is increasingly recognized as more than one disease and is characterized by cytogenetic, molecular, and proliferative heterogeneity. While novel agents and combinations are rapidly redefining the treatment paradigm, patient outcomes vary based on risk stratification.

More information

Comprehensive testing, simplified

Created in conjunction with Mayo Clinic’s multiple myeloma clinical practice, mSMART uses flow cytometry, FISH, and the latest consensus to determine a patient’s genetic risk of developing multiple myeloma. This approach better informs individualized treatment plans and provides clinicians with a comprehensive and correlated patient profile.

In addition to the mSmart evaluation, Mayo Clinic Laboratories now offers comprehensive FISH testing for diagnosis and risk stratification of multiple myeloma. Our approach to fluorescence in situ hybridization (FISH) testing is designed to simplify the ordering process by providing diagnostic panels that include all appropriate genes.

Key testing


After diagnosis or amyloidosis suspicion

By weighing M-proteins, we overcome electrophoresis’s limitations in detection and provide the most accurate understanding of a patient’s M-proteins. This novel MASS-FIX testing also helps healthcare providers understand their patients’ risk of progression to multiple myeloma, AL amyloidosis, or other diseases. This level of insight is not possible with traditional testing methods. 

Key testing


Since the early 2000s, the average length of survival for patients with multiple myeloma, from time of diagnosis, has more than tripled to more than five years. While the use of monoclonal therapies has benefited patients greatly, it presents a unique challenge for laboratories, as these therapies can cause interference with traditional gel immunofixation testing methods. The MASS-FIX methodology easily overcomes this issue for a majority of patients.

More information

MALDI-TOF MS testing provides:

  • Increased sensitivity for early identification of myeloma relapse.
  • Verifying if a patient’s IgG kappa mass is caused by monoclonal therapeutics or residual disease.
  • Convenient, cost-effective, and clinically relevant information.
  • Industry-leading turnaround times for results.

Key testing

  1. Rajkumar SV, Kyle RA, Therneau TM, et al. Serum free light chain ratio is an independent risk factor for progression in monoclonal gammopathy of undetermined significance. Blood. 2005;106(3):812-817
  2. Katzmann JA, Dispenzieri A, Kyle RA, et al. Elimination of the need for urine studies in the screening algorithm for monoclonal gammopathies by using serum immunofixation and free light chain assays. Mayo Clin Proc. 2006;81(12):1575-1578
  3. Mills JR, Kohlhagen MC, Dasari S, et al. Comprehensive assessment of  M-proteins using nanobody enrichment coupled to MALDI-TOF mass spectrometry. Clin Chem. 2016 Oct;62(10):1334-1344. 
  4. Milani P, Murray DL, Barnidge DR, et al. The utility of MASS-FIX to detect and monitor monoclonal proteins in the clinic. Am J Hematol. 2017;92:772-779.  
  5. Abeykoon JP, Murray DL, Murray I, et al. Implications of detecting serum monoclonal protein by MASS-fix following stem cell transplantation in multiple myeloma. Br J Haematol. 2020 Nov. 
  6. Dispenzieri A, Larson DR, Rajkumar SV, Kyle RA, Kumar SK, Kourelis T, Arendt B, Willrcih M, Dasari S, Murray D. N-glycosylation of monoclonal light chains on routine MASS-FIX testing is a risk factor for MGUS progression. Leukemia. 2020 Oct;34(10):2749-2753.
  7. Kourelis T, Murray DL, Dasari S, et al. MASS-FIX may allow identification of patients at risk for light chain amyloidosis before the onset of symptoms. Am J Hematol. 2018;93(11):368-E370.   
  8. Kumar S, Murray D, Dasari S, et al. Assay to rapidly screen for immunoglobulin light chain glycosylation: a potential path to earlier AL diagnosis for a subset of patients. Leukemia. 2018 Jan;33(1):254-257. 
  9. Mellors P, Binder M, Ketterling R, et al. Metaphase cytogenetics and plasma cell proliferation index for risk stratification in newly diagnosed multiple myeloma. Blood Adv. 2020 May;4(10):2236-2244. 
  10. Mills JR, Barnidge DR, Dispenzieri A, and Murray DL. High sensitivity blood-based M-protein detection in sCR patients with multiple myeloma. Blood Cancer J. 2017;7(590).
  11. Mills JR,  Kohlhagen MC, Willrich MAV, et al. A universal solution for eliminating false positives in myeloma due to therapeutic monoclonal antibody interference. Blood. 2018 Aug;132(6):670-672. 
  12. Murray DL, Puig N, Kristinsson S, et al. Mass spectrometry for the evaluation of monoclonal proteins in multiple myeloma and related disorders: an International Myeloma Working Group Mass Spectrometry Committee Report. Blood Cancer J. 2021:11 (24).
  13. Dispenzieri et al, , Mass-Fix predicts for PFS and OS than standard methods among myeloma patients participating on the STAMINA trial,  Blood Cancer Journal, 12(2), 2022 page 27.
  14. Dearman BA, Stefka AT, Jiang K, McIver A, Kubicki T, Jasielec JK, Jakubowiak AJ. Measurable residual disease assessed by mass spectrometry in peripheral blood in multiple myeloma in a phase II trial of carfilzomib, lenalidomide, dexamethasone and autologous stem cell transplantation. Blood Cancer J. 2021 Feb 5;11(2):19. doi: 10.1038/s41408-021-00418-2. PMID: 33563912; PMCID: PMC7873068.
  15. Puig N, Contreras MT, Agulló C, Martínez-López J, Oriol A, Blanchard MJ, Ríos R, Martín J, Iñigo MB, Sureda A, Hernández MT, de la Rubia J, González-Calle V, Krsnik I, Cabañas V, Palomera L, Moraleda JM, Bargay J, Cedena MT, Paiva B, Rosiñol L, Bladé J, San Miguel J, Lahuerta JJ, Mateos MV. Mass spectrometry vs immunofixation for treatment monitoring in multiple myeloma. Blood Adv. 2022 Jun 14;6(11):3234-3239. doi: 10.1182/bloodadvances.2021006762. PMID: 35157768; PMCID: PMC9198943.

Fill out the form below and one of our specialists will be in touch.

(BETA) Choose a language to view this content in:
About the translation.